Sir: The omission of the discovery of penicillin from the New Millennium Experience Company's highlights of the last 1,000 years seems incredible ("Millennium defined by a sandwich", 17 December). Alexander Fleming's discovery and its development by Howard Florey and Ernst Chain revolutionised medicine and affected for the better the lives of every one of us. It began the antibiotic age in medicine which has saved countless lives. It is a sad reflection on those organising the millennium celebrations that they should rate the sandwich a higher achievement.